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Blue Topaz: Birthday Blue
Blue topaz has become one of the most popular gemstones
on the market today, due to its clarity, durability,
availability and affordable cost. Yet it is a shade
of topaz rarely found in nature. The stones watery
blue color is most often created through a combination
of heat treatment and irradiation.
Topaz is one of the well-known pegmatite minerals that
also includes beryl and tourmaline. Blue topaz is the
birthstone for December - and is also the recommended
gemstone for couples celebrating their fourth wedding
anniversary.
Blue topaz has a definite, uniform color ranging from
sky blue to Swiss blue. It is sometimes confused with
the more costly aquamarine - yet whereas aquamarine
sometimes has a greenish-blue or bluish-green tint,
blue topaz will always look blue or bluish gray. The
one exception is for surface-enhanced topaz, a process
introduced in 1998 that enhances the stonesEappearance
and brings out colors such as blue to greenish-blue
to emerald green.
Most blue topaz starts life as a colorless or slightly
tinted topaz from places like Brazil, Mexico, Nigeria,
Sri Lanka and China. It is then irradiated (to incite
the color change) and heated (to stabilize the change).
The result is a permanent aqua shade. To get deep blue
color out of topaz, treaters use neutron bombardment
in a nuclear reactor and market the final product under
the name "London blue." In fact, neutron bombardment
is the only means by which to produce smaller calibrated
stones with deep color.
Despite the stones exposure to irradiation, experts
say it poses no health hazard whatsoever to the wearer.
In addition to blue, the stone comes in a variety of
colors, including golden yellow, orange-yellow, reddish-orange,
sherry red, deep pink, honey brown, light green, and
many shades in between.
Topaz holds the distinction of being the gemstone thought
to have the widest rage of curative powers. According
to legend, the stone can dispel enchantment and improve
the eyesight. The ancient Greeks believed that it had
the power to increase strength and make its wearer invisible
in times of emergency. Topaz is also said to change
color in the presence of poisoned food or drink. Throughout
history, different cultures have believed that the stone
could cure insomnia, asthma and hemorrhages; bring friendship;
promote patience and a pleasant disposition, and ensure
fidelity. To the ancients, it was also a symbol of love
and affection and was even thought to ward off sudden
death.
With a ranking of "8" on the Mohs scale of
hardness, blue topaz is exceptionally strong and durable
and well-suited to everyday wear. However, it should
be protected against hard blows which can split, crack
or chip it.
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